Object
An object is an instance of a class stored in a set of memory locations.
Related concepts: ClassTypeValue
Closest Wikipedia entry: Object-oriented programming
Misconceptions about Object31 documented Misconceptions
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AssignmentCopiesObject — Java
Assignment copies the objectChainedMethodsNotCalledFromOutside — Java
Chained methods are all called on the object at the beginning of the chainEqualityOperatorComparesObjectsValues — Java
o==p compares the objects referred to by variables o and pEqualsComparesReferences — Java
o.equals(p) compares the references stored in the variables o and pFrameIsClassInstance — Java
A stack frame is the same as an instance of a classMethodAsField — Java
Each object contains its own special fields for all of its methodsMultiReferenceVariable — Java
A reference variable can point to multiple objectsNestedObjectsImplyNestedClasses — Java
If objects are part of a containment hierarchy, their classes are nested, tooNoFieldInheritance — Java
An object contains only the fields declared in its classNoFieldlessObjects — Java
Objects without instance variables can't existNoInsideMethodCallInConstructor — Java
It is foirbidden to call other methods on the same object while inside its constructorNullIsObject — Java
null is an objectSuperclassObjectAllocated — Java
When instantiating an object of a subclass, an object of a superclass is also allocatedThisAsField — Java
this is a special field in the objectThisAssignable — Java
One can assign to thisThisExistsInStaticMethod — Java
this is a local variable, also in static methodsVariablesHoldObjects — Java
A variable of a reference type contains a whole objectAccessingInexistentPropertyError — JavaScript
Accessing a non existent property on an object produces an errorAssignmentCopiesObject — JavaScript
Assignment copies the objectEqualityOperatorComparesObjectsValues — JavaScript
The equality operator compares two objects' valuesIdentifierAsStringInBracketNotation — JavaScript
An identifier used to access a property with the bracket notation is treated as a stringNoBracketNotationForObjects — JavaScript
Square brackets cannot be used to access properties of an objectNoGlobalObject — JavaScript
There isn't a global objectNullIsObject — JavaScript
null is an objectObjectAsParameterIsCopied — JavaScript
Objects are passed by valueThisAssignable — JavaScript
One can assign to thisAssignmentCopiesObject — Python
Assignment copies the objectObjectsMustBeNamed — Python
A variable is needed to instantiate an objectSelfAssignable — Python
Reassigning self changes the object on which a method is calledVariablesHoldObjects — Python
A variable contains a whole objectEqualityOperatorComparesListIdentities — Scratch
(list a) = (list b) compares the identities of list a and list b